Hypo-Segmented Heterogeneous Boron Distribution Application in Boron Neutron Capture Therapy

Heterogeneous boron concentration distribution is the primary determinant that must be considered in boron neutron capture therapy (BNCT) dose calculations. However, taking into account the slip in BNCT dose calculation and assessment come from fusion of different image modalities and the partial volume effect of image voxel differences, it is necessary to reduce these errors when building a highly realistic computational model in order to provide high-confidence dose results. This article uses hypo-segmented heterogeneous boron distribution dose calculation to apply to brain tumor and head and neck cancer cases to evaluate dose cold spots in tumor and hot spots in organs at risk. Using hyper-segmented boron distribution dose results as a reference benchmark to compare with hypo-segmentation results, the mean tumor dose difference between the two is within 1.6%, and the D ₈₀ difference is within 2.3%. Significant differences in maximum and minimum doses to the region of interest are expected between hyper- and hypo-segmentation methods, but the dose-volume histogram for both are close to each other. Then, post-BNCT follow-up images were compared with dose maps of hyper- and hypo-segmented boron distribution. The dose distribution echoes clinical response, indicating that the hypo-segmented boron distribution method has evaluation properties.